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Previous biotesting data on a model of rooting leaf and stem cuttings of beans proposed by the authors as a specific test for auxins allowed a conclusion that the auxin activity is inherent for benzyl alcohols, benzylamines and their quaternary ammonium derivatives. Using a quantitative molecular biotest on a model of three-day-old seedlings of the transgenic Arabidopsis thaliana L. transformed with a construct expressing the β-glucuronidase gene under the control of the auxin-sensitive DR5 semisynthetic promoter it was found that these compounds did not have the auxin activity. We showed that the biotest on the model of rooting of leaf and stem bean cuttings was nonspecific towards auxins and can detect the rhizogenic activity rather than the auxin activity of the compounds under study. Using the biotest on the rhizogenic effect of ten-day-old pea seedlings (Pisum sativum L.) of the Six-Weekly variety we demonstrated that the stress-protectors-phytoregulators under study were comparable by the rhizogenic effect with indole-3-acetic acid (IAA), a natural auxin, although they are not auxins. This is consistent with the previous data on the rhizogenic activity obtained on the models of rooting of leaf and stem cuttings of beans and germination of barley seeds. Thus, we showed that oxybenzyl OBzl and aminobenzyl NHBzl groups were new structural elements that ensured a high rhizogenic activity of the chemical regulators of plant growth.

A kinetic study of ethylene oxidation to acetaldehyde by p-benzoquinone in the Pd(OAc)2–HClO4−LiClO4–CH3CN–H2O system has been carried out under conditions when palladium(II) cationic complexes exist at a molar fraction of water of 0.67 and 30°С. For a reaction that mostly lead to the formation ofPd(CH3CN)(H2O) 3 2+ two-route mechanism and a kinetic model have been proposed that describe adequately the experimental dependence of the reaction initial rate on the concentration of p-benzoquinone, HClO4, and palladium. The model takes into account previous findings on the H2O/D2O and C2H4/C2D4 kinetic isotope effects and the important role of Pd(0) quinone complexes.

The first representatives of 3-trifluoromethyl-2-(dialkoxyphosphoryl)imidazo[1,2-a]pyridines have been synthesized by the reaction of N-(pyridin-2-yl)-perfluoropropanimidoyl chlorides with triethyl phosphite.

The work deals with the problem of choosing the optimal of gas and gas-condensate wells pattern. Numbers of three-dimensional hydrodynamic models based on multi-variant calculations and economic analysis select the optimal wells pattern. However, creating a full-scale models is not always appropriate, for example, in case of low exploration at the initial development stage, the lack of investigation methods of reserves difficult to recover. In this case justification of the wells pattern should be based on other principles. The article suggests a method of justification of the pattern arrangement, based on sectoral hydrodynamic models calculations. The advantages of sectoral models in case of low-data are the creation of local geological model based on the exploration wells data, little calculation time, interactive model changes. However, sectoral modeling has a several questions, for example the size of the sector or the boundary conditions. In the solution of the well location problem the modeling sector size determines the distance between the wells, which influences on the dynamics of wells technological parameters, the development time, cost effectiveness of the project. The main idea of the proposed methods is to analyze of wells production in non-stationary filtration models (the maximum production rate in a minimum development time). The pseudo-stationary radius is based on the economic analysis.

An integrated neuroreconstructive approach to stimulating the pathogenetic mechanisms of a vegetative state developed due to a severe traumatic brain injury (TBI) is suggested. It has been shown that a faster and more pronounced therapeutic effect, compared with conventional therapies, could be achieved through the application of transtimpanal chemical vestibular dereception and transcranial micropolarization. The results of neurophysiological in-depth examination in dynamics have shown that over time interregional cortical interactions become more intense, “rigid,” and “tight” in patients with a vegetative state, while the temporal-parietal-occipital areas begin to dominate in the organization of these interactions in the cortex of both hemispheres. It is assumed that the vestibulothalamic tract, owing to its anatomical location, appears to be the least vulnerable under the conditions of brain stem dislocation due to a severe TBI. As a result, vestibular afferentation appears to become a predominant kind of afferentation for generating interregional cortical interactions. A pathological functional system develops on the basis of this afferentation, blocking other functional systems in the damaged brain. The suggested therapies significantly reduce the amount of vestibular afferent inputs and open a possibility for restoring more effective afferent interactions. This significantly facilitates the functioning of the brain as a multimodal analyzer.

Kinetic isotope effects (KIE) have been measured for oxidation reactions of ethylene by p-benzoquinone in Pd2+—MeCN—H2O—HClO4 system. Under the conditions of preferred formation of complex Pd(MeCN)(H2O)3 2+ the ratio between the initial reaction rates $$R_{{C_2}{H_4}} 0/R_{{C_2}{D_4}} 0$$ is equal to 1.14±0.06 and is close to the KIE for classical chloride systems. Based on the obtained results and previous data for C2H4—C2D4 and H2O—D2O (0.97±0.12) systems, the slow step was proposed in the reaction mechanism–a trans-addition of water molecule to the cationic p-complex LPd(H2O)2(CH2CH2)2+ with formation of metalcarben-ium ion solvated by water molecule (LPd(H2O)2(CH2CH2O+H2)+).

Three-component reaction of Piracetam, methyl trifluoropyruvate and 1,3-binucleophiles, such as 6-aminouracils, 6-aminothiouracils, 4-(4-tolylamino)pent-3-en-2-one and N-substituted ureas, has been studied. This reaction resulted in fluorinated heterocyclic derivatives of Piracetam.

An approach to the modification of the known antimicrobial drug, streptocide, with fluorine-containing five-membered heterocycles is proposed. The reaction of the generated in situ methyl 2-[4-(N-acetylamino)phenylsulfonyl]imino-3,3,3-trifluoropropionate with 1,3-C,N- or 1,3-N,N-binucleophiles and subsequent hydrolysis of the resulting products furnished different novel fluorine-containing heterocyclic derivatives of streptocide, including fused heterocycles.

Standard reduction potentials were studies as functions of the electronegativity (EN) of monoatomic ions. The ENs of anions are almost equal to the ENs of the corresponding atoms. Metal cations with lower reduction potentials are characterized by higher ENs.

Reaction of arenesulfonylimines of methyl trifluoropyruvate with 1,3-C,N-and-N,N-binucleophiles led to a variety of N-sulfonylated fluorine-containing heterocycles, including the fused ones.

Cyclocondensation of methyl 2-(5-methylisoxazol-3-yl)imino-3,3,3-trifluoropropionate with 1,3-binucleophiles such as benzamidines, aminothiazoline, and 2-aminocrotonic acid nitrile results in trifluoromethyl-containing 3,5-dihydro-4-ones, 2,3-dihydro-6H-imidazo[2,1-b]thiazol-5-one, and 4,5-dihydro-1H-pyrrole-3-carbonitrile.

Reactions of acylimines of methyl trifluoropyruvate with C,N-bisnucleophiles gave fluoro-containing heterocycles including the 5-oxo-4,5-dihydro-1H-pyrrole fragment.

Reactions of acylimines of hexafluoroacetone and methyl trifluoropyruvate with 2-aminothiazolines afforded fluorine-containing heterocycles of two structural types: 6,7-dihydro-2H-thiazolo[3,2-a][1,3,5]triazines and 2,3,5,6-tetrahydroimidazo[2,1-b]thiazoles.

The structural analogs of α -aminoacids, α -aminophosphonic acids and their esters, are widely studied as biologically active substances [1]. At the same time, among the numerous publications of the last twenty years there are only a few communications devoted to biological activity of fluorinated α -aminophosphonates, although it is well known that inclusion of fluorine atoms and fluorine-containing substituents into molecules of organic substances results in profound changes of chemical and physicochemical properties and, consequently, the biological activity of these substances. In particular, it was shown that some fluorinated esters and phosphin-oxides inhibited cholinesterases [2, 3] and thrombin [4], in contrast to their nonfluorinated analogues. In this paper, the results of studies of interaction of fluorinated α -aminophosphonates (FAPs, 3a ‐ 3h ) with four serine hydrolases are presented. Compounds 3a ‐ 3h were synthesized according to the scheme shown below

The importance of six theoretically calculated molecular parameters in the antigibberellin (retardant) activity of quaternary ammonium salts is studied using regression analysis. A bioassay system based on cell culture of fungus Gibberella fujikuroi is used to determine the activity. In the case of N,N,N-trimethyl-N-(2-hydroxyethyl)ammonium chloride (choline) and N,N,N-triethyl-N-(2-hydroxyethyl)ammonium chloride (N,N,N-triethylcholine) derivatives with linear structure, the polarizability, proton acceptor activity, and lipophilicity of these compounds exert the largest effect on the antigibberellin activity. The antigibberellin activity of more sterically hindered N,N-dialkylpiperidinium salts was mainly defined by the steric parameter, while the polarizability, proton acceptor activity, and (through them) lipophilicity exert a lesser effect. Other parameters are of minor importance for the three groups of compounds studied. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 6; see also http://www.maik.ru.

A combined approach to neuroreconstructive effects on pathogenesis mechanisms of vegetative state that develops as a result of severe traumatic brain injury (TBI). It is shown that under the influence of chemical transtimpanal vestibular dereception and transcranial micropolarization (TDCS) accelerated and more pronounced therapeutic effect than conventional therapy. Neurophysiological in-depth examination of the dynamics shows that over time in patients in a vegetative state, picking up the intensity, "tension" and "rigidity" of inter-regional cortical interactions in the organization that are beginning to dominate the area TPO cortex of both hemispheres. It is suggested that in the dislocation of the brain stem in severe TBI is vestibulotalamic tract, thanks to its anatomical location, is the least vulnerable. As a result, the prevailing afferentation forming inter-regional cortical interactions is vestibular afferent impulses. On its basis the pathological functional system, blocking the work of other functional systems of the damaged brain. Suggested treatments significantly reduce the amount of vestibular afferent flow and open up the possibility of recovery of more effective interafferential interactions. This greatly facilitates the work of the brain as a multimodal analyzer.

Et3N-catalyzed cyclocondensation of imines (I) with acetylacetone provides dihydrofuranones (III) in good yields.

A convenient method is proposed for obtaining difficultly available derivatives of 2-amino-5-chloromethyl-2-thiazoline by the cyclization of N-allythioureas under the action ofα-chloronitrosoalkanes. It is assumed that the reaction proceeds as a halogenophilic process leading to the intermediate formamidinesulfenyl chloride which is rapidly and selectively cyclized with the formation of 2-amino-2-thiazoline derivatives.

Intramolecular cyclization of 1-allyl- and 1-methallyl-6-amino-2-thiouracils afforded 5-amino-2,3-dihydrothiazolo[3,2-a]pyrimidin-4-ones, whose structures were proved by chemical transformations.

Imines, generated in situ from aminothiadiazoles (I) and methyl trifluoropyruvate (II) in the presence of the dehydrating system pyridine/thionyl chloride, undergo cyclocondensation with 1,3-C,N- and 1,3-N,N-binucleophiles such as N-substituted ureas (III), aminocrotononitrile (V), N-substituted aminouracil (VIIa) and aminothiouracil (VIId), N-substituted aminocyclohexenones (IX), and benzylbenzamidine (XI).

81 The use of anticholinesterase compounds in medi cine, veterinary practice and agricultural chemistry is based on their common mechanism of action, which is determined by the inhibition of acetylcholinesterase (EC 3.1.1.7, AChE) [1]. Many cholinesterase inhibi tors, in addition to AChE, interact with other serine esterases, that can lead to both toxic and therapeutic effects [2]. Toxic and therapeutic effects resulting from the inhibition by organophosphorus compounds (OPCs) of four serine esterases—acetylcholinest erase, neuropathy target esterase (EC 3.1.1.5, NTE), butyrylcholinesterase (EC 3.1.1.7, BChE), and car boxylesterase (EC 3.1.1.1, CaE)—are shown in Scheme 1, where the effects that determine the toxic action of OPCs are shown in italic.

2-Hydroperfluoropropyl azide CF3CHFCF2N3, 1, an inexpensive, readily available, and stable (easy to store) compound, is suggested as an effective fluorinating reagent for different classes of trivalent organophosphorus compounds in accordance with the general scheme R3P R3PF2. Generally, the reactions are performed without solvent, the highly volatile CF3 CHFCN being the main by-product. The fluorination is usually an exothermic process, but slight heating is necessary in the case of alkyldifluorophosphites. The unusual Arbuzov rearrangement, accompanied by isomerization of an isobutyl or neopentyl group into a tert-group, ROPF2 t-R′POF2, under the action of a catalytic amount of 1, was observed.

Hydroxamic acid derivatives exhibit a broad spec- trum of biological activity. They include substances with the fungicidal, antibacterial, insecticidal, acari- cidal, and rodenticidal activities, plant-growth regula- tors, herbicides, animal-growth stimulators, and both inhibitors and reactivators of enzymes. final acetone concentration in the substance-containing and control media was 10 ml/l. The prepared agar was poured into Petri dishes with an internal diameter of 9 cm (15 ml per dish) and cooled. Mycelium pieces of three-day-old fungal cultures were inoculated into the nutrient medium and kept at 25 ∠ 1i C for three days. Then, the diameters of fungal colonies were measured to determine the extent of the mycelium growth inhi- bition as compared to the control. In all series, tri- adimephon (3,3-dimethyl-1-(1H-1,2,4,-triazolyl-1)-1- (4-chlorphenoxy)butanon-2) was used as a reference substance. The results of the tests are shown in Table 2. Synthesis, spectral characteristics, and physico- chemical properties of the compounds used were previ- ously described in detail (7). To study the structure-activity relationships, several types of descriptors were used. The latter were calcu- lated from the molecular mechanical (MMC) and quan- tum-chemical (AM 1) calculations of molecules, the logarithm (log P ) of the coefficient of the compound distribution in the octanol-water system, and the pres- ence of either aliphatic or aromatic substituents.

Perfluoroisobutylene and perfluoropropylene react with N-silylamidophosphites by an Arbuzov reaction to form the respective phosphazo compounds that contain a P-C bond.

Structure, stability and some reactions of the obtained adducts of α-dichloronitrosoalkanes with dichlorophosphines are discussed. One-pot synthesis of O-(alkylchloroformoimino)phosphonic acid chlorides and esters is described.

The reaction of (III) was demonstrated by elemental analysis, NMR spectroscopy on a Bruker CXP-200 spectrometer, and conversion to nitrile (IV). N-Methyl-N-(pentafluoropropen-2-yl)-O-ethylcarbamate (III). A sample of 20.92 g (I) in 40 ml CHzCI 2 was added dropwise in an argon atmosphere to 9.95 g (II) in 20 ml CHzCI 2 at 0~ The reaction mixture was stirred for 2-3 h, evaporated, and fractionated to give I0.19 g (49.6%) (III), bp 132-134~ nD 2~ 1.3596. PMR spectrum (6, ppm): 1.27 t (3H, CH3), 3.0 s (3H, CH3N), 4.18 m (2H, CHz), I~F NMR spectrum (6, ppm): -5.5 m (IF, CF2), -2.5 m (IF, CF2), 13.0 m (3F, CF3). N-Methyl-N-(l-cyano-2,2,2-trifluoroethyl)-O-ethylcarbamate (IV). A sample of 2.18 g hexamethyldisilazane in 5 ml ether was added to a solution of 3.0 g (III) in I0 ml ether. The reaction mixture was heated in a sealed ampule for 20 h at IO0~ Ether was evaporated and the residue was fractionated to give 1.48 g (54.8%) (IV), bp 86-88~ (I0 mm), nDZ~ 1.3834. PMR spectrum (6, ppm): 1.33 t (3H, CH3), 3.14 br.s (3H, CH3N), 4.24 m (2H, CH2), 6.11 m (IH, CH). 19F NMR spectrum (6, ppm): 5.43 s. The elemental analysis data were in satisfactory accord with the calculated values.